In this paper, we report synthesis and radical polymerization of new organic－inorganic hybrid monomers, zinc bis(allyldithiocarbamate)s. All of the monomers have no absorption at visible region. Their n_D values, estimated from the concentration dependence of the n_D values of the monomers, were higher than 1.60. A white insoluble product was obtained by radical homopolymerization of zinc bis(diallyldithiocarbamate) (Zn(DADTC)₂). Moreover, radical copolymerization of Zn(DADTC)₂ with methyl methacrylate and styrene gave colorless products. The resulting polymers were tolerant to treatment with organic solvents.

Silver particles have been formed from silver nitrate by chemical reduction in phenolic resin aqueous solution under basic conditions. The silver particles were covered with phenolic resins and highly dispersed in the materials. The materials are composed of metals and resins in nanometer scale and expected to show new functional properties. We named this hybrid material as metal hybrid resin (MHR). It was found that mechanical strength of cured MHR was higher than that of general phenolic resins and the metal adhesion property of MHR was improved. From these results, MHR is expected to show high performance property in comparison with general phenolic resins.

In recent years, the epoxy resin composition capable of quick curing has been required from the point of view of energy conservation. For the purpose, cationic polymerization has been used as a curing system. We have already reported that Bisphenol A-type β-methyl diglycidyl ether had high reactivity and provided cured materials with flexiblity and low T_g in cationically curing system. These results stimulated us to design novel β-methylglycidyl ether-type epoxy resins with various molecular structures, which might be able to control the properties of cured materials. Here we synthesized four β-methyl diglycidyl ether-type epoxy resins with different central skeleton and investigated their reactivity and physical properties of the cured product in order to clarify the influence of center skeleton on the curing behavior and the physical properties of the cured product. The results of DSC analyses revealed that β-methyl diglycidyl ether-type epoxy resins having an electron-donating property in the central skeleton had a high curability. Furthermore, it was clarified that the hardness and T_g of cured materials could be controlled by the concentration of epoxy group in the composition and the rigidity of the central skeleton

Recently, bio-based polyurethanes have received much attention as environmentally benign materials. This study deals with a dimer acid-containing polyurethane ionomer showing good elastic properties. A polyester polyol was prepared by the reaction of dimer acid with an excess of 1,4-butanediol. The polyol was reacted with 4,4’-diphenylmethanediisocyanate and N-methyldiethanolamine, and subsequently, the reaction of the resulting polyurethane with 1,3-propanesultone produced the polyurethane ionomer possessing the zwitterionic group. The FT－IR and DSC data suggest the aggregation of the zwitterionic group in the polyurethane. Mechanical properties were improved by the introduction of the zwitterionic group.

In this article, we report a novel reversible crosslinking－decrosslinking system consisting of a polymer bearing vicinal tricarbonyl moieties in its side chain and poly(ethylene glycol)s (PEGs). A mixture of the tricarbonyl polymer and PEG (M_n＝600－20,000, 0.1－3.0 equiv of OH groups relative to the vicinal tricarbonyl moieties) in CH₂Cl₂ spontaneously turned into an orange-colored gel, in which a network structure was formed through hemiketal linkage. Conversely, the resulting networked polymer could be decrosslinked by treatment with water-containing solvent to recover the linear vicinal tricarbonyl polymer as its hydrate form in up to 96% yield. Following dehydration process by heating at 100 ℃ under reduced pressure regenerated the original vicinal tricarbonyl polymer.

This paper reviews synthesis and property of UV-curing materials based on hyperbranched polymers containing radical polymerizable groups acrylate and methacrylate at the ends. The hyper branched polymers could be synthesizded by A₂ + B₃ and AB₂ methods by various polymerization systems, such as ene-thiol reaction, [2 + 2]cycloaddition reaction, radical polymerization, polyaddition reaction and polycondensation reaction. The radical-polymerizable groups could also be introduced into the synthesized hyperbranched polymers to give corresponding UV-curing hyperbranched polymers. Furthermore, UV curing reactions of the synthesized UV-curing hyperbranched polymers were examined in the presence of photo-radical initiators in the film state by the UV irradiation and followed by heat at elevated temperature, yielding the corresponding cured films smoothly. The thermal stability and mechanical property of the obtained cured films were also examined, and their properties were superior to those of corresponding linear UV-curing polymers.